1. Field of the Invention
This invention pertains generally to fuel injectors for internal combustion engines, and more particularly to a fuel injection apparatus which delivers fuel to an engine cylinder through a plurality of injector ports disposed in a circular fashion around the cylinder, the apparatus being conveniently adapted to fit between an engine block and a cylinder head.
2. Description of the Background Art
Fuel injection in internal combustion engines has provided an efficient alternative to traditional carburetion methods for a number of years. By feeding fuel directly to the cylinders rather than going first through an intake manifold, fuel injection systems avoid the "lag" commonly experienced with carburetors. Hence fuel injection provides an efficient means of fueling an internal combustion engine and achieving optimum performance.
A traditional method of fuel injection has been to position the fuel ports in the cylinder head, thereby injecting fuel downward from the top of the cylinder. Such an arrangement of the fuel ports produces incomplete and inefficient burning of the vapor mixture during combustion, because the fuel vapor temperature furthest from the fuel injector drops significantly, before combustion is complete. This results in carbon and unburned fuel being expelled in the exhaust.
Various alternative approaches to traditional fuel injection can be found. For example, German patent 952,042 issued Nov. 8, 1956, discloses a fuel injection system having circularly disposed injector ports which inject fuel from the side of the cylinder. U.S. Pat. No. 4,970,270 issued to McKay et al. on Dec. 13, 1988, discloses injecting fuel through one side of the cylinder of an engine where the fuel is sprayed in a number of streams. The streams are directed, upward, downward and across the cylinder. British patent 401,796 issued to Hasson et al. on Nov. 23, 1933 discloses injecting fuel through opposing sides of the cylinder of an engine, where multiple sprays of fuel fan out across the top of the piston. British patent 362,146 issued to Lang on Dec. 3, 1931, discloses the use of "plugs" rather than fuel injectors. The plugs are inserted into the side of the cylinder in circular fashion for purposes of spraying a circular pattern of fuel. In addition to functioning to deposit fuel, the plugs also serve as auxiliary compression chambers. U.S. Pat. Nos. 1,644,557 and 1,544,524 issued on Oct. 4, 1927 and Jun. 30, 1925 respectively, both disclose side injection systems which are disposed between the cylinder head and block of an engine. U.S. Pat. No. 2,805,654 issued to Jacklin on Sep. 10, 1957, discloses an opposed piston two-cycle engine which has a means for introducing fuel to the cylinder in a circular fashion. U.S. Pat. 3,023,743 issued to Schauer on Mar. 6, 1962, discloses an opposed piston engine with circular inlet ports disposed around the cylinder wall.
In addition, the following U.S. Pat. Nos. disclose a variety of other types of fuel injection systems and are of interest: 4,702,414, 3,664,818, 4,359,191, 4,070,826, 4,858,578, 4,858,579.
The fuel injection devices disclosed in the foregoing patents still do not provide for complete and efficient combustion of the fuel, add to the size and complexity of the engine, and increase the amount of maintenance required. Therefore, there is a need for an apparatus which provides for injection of fuel into the combustion chamber evenly, efficiently and at a uniform pressure, which does not add to the complexity or size of the engine, and which is easy to maintain. The present invention satisfies those needs, as well as overcomes the deficiencies in fuel injection devices heretofore developed.
The foregoing patents reflect the state of the art of which the applicant is aware and are tendered with the view toward discharging applicant's acknowledged duty of candor in disclosing information which may be pertinent in the examination of this application. It is respectfully stipulated, however, that none of these patents teach or render obvious, singly or when considered in combination, applicant's claimed invention.